#include <iostream>
#include <vector>

using namespace std;

class Solution {
public:
    int minDistance(string word1, string word2) {
        vector<vector<int>> dp(word1.size() + 1, vector<int>(word2.size() + 1, 0));
        for (int i = 1; i <= word1.size(); i++) {
            dp[i][0] = i;
        }
        for (int i = 1; i <= word2.size(); i++) {
            dp[0][i] = i;
        }
        for (int i = 0; i < word1.size(); i++) {
            for (int j = 0; j < word2.size(); j++) {
                if (word1[i] == word2[j]) {
                    dp[i + 1][j + 1] = dp[i][j];
                } else {
                    dp[i + 1][j + 1] = min(min(dp[i][j], dp[i][j + 1]), dp[i + 1][j]) + 1;
                }
            }
        }
        return dp.back().back();
    }
};